Adjustable strap



FIG. 1 is a perspective view of an adjustable strap showing my new design;

FIG. 2 is a top plan view, the opposite side being a mirror image;

FIG. 3 is a front elevational view;

FIG. 4 is a rear elevational view;

FIG. 5 is a left-hand side view thereof; and,

FIG. 6 is a right-hand side view thereof.

The broken line showing of a cap is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for an adjustable strap, as shown and described. 